In a portable power tool such as a disc grinder, in order to reduce the vibrations that occur during operation, which might otherwise be transmitted from the power tool body to the handle (or switch handle) connected to the tool body, it is the general practice to dispose a vibration-proof mechanism at the connecting portion between the tool body and the handle. In this power tool having the vibration-proof handle, it is also conventional to clamp an elastic member in the connecting portion between the power tool body and the handle, so that the vibrations from the tool body may be absorbed by the elastic member. A power tool having such a vibration-proof handle is disclosed in Patent Document 1, as follows.
[Patent Document 1] Japanese Patent No. 2,534,318
However, the power tool having the vibration-proof switch handle, as disclosed in Patent Document 1, is troubled by the complicated assembling process of interposing the elastic member between the power tool body and the handle. Another problem is that the length of the power tool body and the handle is enlarged in the direction of the center axis so that the power tool itself is large. Therefore, a power tool which can be manufactured by a relatively simple assembling process and which has a vibration-proof handle, was developed and disclosed in Japanese Patent Application No. 2004-315029.
In the proposed technique of this Patent Application, however, the structure permits the load of the handle to be concentrated at an elastic member. If the deformation of the elastic member by a load is excessively large, the elastic member is permanently deformed and deteriorated due to aging. This raises a problem that play (or looseness) occurs between the elastic member and the power tool body or the handle.
Moreover, dust such as iron powder produced at the working site, enters the arm-sliding portion between the handle holder portion formed integrally with the power tool body and the arm portion of the handle, causing wear to the handle holder portion and the handle arm portion together with the aforementioned deterioration, this wear reduces the operability of the power tool.
There is another demand for reducing the length of the power tool body and the handle in the direction of the center axis.